Traditionally gold prospectors have used dredges, sluice boxes, gold pans, etc. for on-site classification and concentration. However, all the above mentioned tools are designed for the principle of in-stream operation, thus leaving many old stream beds or glacial deposits virtually untouched.
Most one-man placer operations have been limited to areas directly adjacent to or within a stream bed itself. In many instances, the values are not limited to this confined area. Therefore, the miner is restricted by his equipment rather than knowledge or intuition as to where deposits may be located.
In the past, most mining for precious metals such as gold has meant high volume production. Now, however, with many regulations in effect and many more in planning stages, there is a need for a small efficient machine that does not require heavy equipment for prospecting or simply working a placer claim on a small scale. Such an apparatus would also be desirable for cleaning up behind a heavy duty dredge or sluice box. It is also desirable to provide an apparatus that will complete total separation of precious metals from placer material. Such an apparatus would eliminate costly separation methods that can also be dangerous (as when retorts are used).
The present apparatus allows for freedom to placer mine some distance from a stream or other water source. The self-contained nature of the present apparatus facilitates total portability for reaching previously inaccessible areas. In addition, because the apparatus may be situated some distance from a water source, the tailings and water discharge do not quickly reenter the stream. The result is the effect on stream bed ecology is minimal, and many government regulations are automatically compiled with.
The present apparatus is also very effective in concentrating values from placer material. Gold, for example, can be recovered without need for expensive additional equipment or dangerous chemicals.